Awake Multimodal Phenotyping for Prediction of Oral Appliance Treatment Outcome

Indications for Dental Specialists for Treating Obstructive Sleep Apnea with Mandibular Advancement Devices: A Narrative Review

Obstructive sleep apnea (OSA) syndrome is characterized by repeated airway collapse during sleep. It determines cardiovascular, pulmonary, and neurocognitive consequences and is associated with several daytime and nighttime symptoms that influence the patient's quality of life. The contribution of the dental specialist in the clinical management of OSA patients entails participating in the screening process as diagnostic sentinels and providing adequate treatment using mandibular advancement devices (MADs). Since the treatment of OSA requires a multidisciplinary approach, including different medical specialists, dentists should have a comprehensive understanding of medical and dental factors that influence the strategy and effectiveness of OSA treatment with MAD. Such expertise is crucial in determining the appropriate treatment indications and helps clinicians establish a consolidated position within the multidisciplinary OSA team. In this regard, this review summarizes the evidence of the clinical indications for MAD treatment and provides the dental specialist with helpful information about medical, functional, and other relevant factors that should be considered during diagnosis, treatment plan, and follow-up stages. Information retrieved was organized and discussed, generating specific domains/queries oriented to the clinical management of OSA patients from the clinical perspective of dental specialists.

Effect of mandibular advancement splint therapy on cardiac autonomic function in obstructive sleep apnoea

PURPOSE

This study aimed to evaluate the effect of mandibular advancement splint (MAS) therapy on cardiac autonomic function in patients with obstructive sleep apnoea (OSA) using heart rate variability (HRV) analysis.

METHODS

Electrocardiograms (ECG) derived from polysomnograms (PSG) of three prospective studies were used to study HRV of patients with OSA before and after MAS treatment. HRV parameters were averaged across the entire ECG signal during N2 sleep using 2-min epochs shifted by 30 s. Paired t-tests were used to compare PSG and HRV measures before and after treatment, and the percent change in HRV measures was regressed on the percent change in apnoea-hypopnea index (AHI).

RESULTS

In 101 patients with OSA, 72% were Caucasian, 54% men, the mean age was 56 ± 11 years, BMI 29.8 ± 5.3 kg/m2, and treatment duration was 4.0 ± 3.2 months. After MAS therapy, there was a significant reduction in OSA severity (AHI, - 18 ± 16 events per hour, p < 0.001) and trends towards increased low-frequency to high-frequency ratio, low-frequency power, and reduced high-frequency power (LF:HF, - 0.4 ± 1.5, p = 0.01; LF, - 3 ± 16 nu, p = 0.02, HF, 3.5 ± 13.7 nu, p = 0.01). Change in NN intervals correlated with the change in AHI (β(SE) =  - 2.21 (0.01), t =  - 2.85, p = 0.005). No significant changes were observed in the time-domain HRV markers with MAS treatment.

CONCLUSION

The study findings suggest that successful MAS treatment correlates with changes in HRV, specifically the lengthening of NN intervals, a marker for improved cardiac autonomic adaptability.

Predictive factors of therapeutic response according to craniofacial skeletal biotype in patients with sleep apnea syndrome using mandibular advancement devices: a pilot study

OBJECTIVES

To evaluate the influence of facial biotype in the therapeutic effect of mandibular advancement devices (MADs) according to polysomnographic records in patients diagnosed with sleep apnea-hypopnea syndrome (SAHS).

MATERIALS AND METHODS

A total of 46 patients were recruited. Patients were classified according to facial biotype (mesofacial, brachyfacial, or dolichofacial). The quantitative variables were described as the arithmetic mean and standard deviation or the median and interquartile range. Hypothesis tests used were Pearson's chi-square, paired-sample Student's t- test, the Wilcoxon test, one-way analysis of variance, Kruskal-Wallis test, and Mann-Whitney U-test. P < .05 was considered statistically significant.

RESULTS

A total of 46 patients were categorized into three facial biotype subgroups with no significant differences among them in age, body mass index, neck circumference, and sex. The respiratory disturbance index (RDI) results were as follows: brachyfacial patients had a reduction to 15 events/h (P < .001), the mesofacial patients had a reduction to 14 events/h (P < .001), and the dolichofacial patients did not show a significant reduction. The oxygen desaturation index (ODI) results were as follows: brachyfacial patients had a reduction in ODI episodes to 45 episodes/h (P = .001), mesofacial patients had a reduction to 18 episodes/h (P = .001). In the brachyfacial group, the number of awakenings with MAD therapy was reduced to 23 events/h (P = .003), while, in the mesofacial group, it was reduced to 37 episodes/h (P = .012).

CONCLUSIONS

The facial biotype influences the effectiveness of MAD therapy and is considered a good predictive factor.

Upper airway morphology in adults with positional obstructive sleep apnea

PURPOSE

To compare the anatomical balance and shape of the upper airway in the supine position between adults with positional obstructive sleep apnea (POSA) and adults with non-positional OSA (NPOSA).

METHODS

Adults diagnosed with OSA (apnea-hypopnea index (AHI) > 10 events/h) were assessed for eligibility. POSA was defined as the supine AHI more than twice the AHI in non-supine positions; otherwise, patients were classified as NPOSA. Cone beam computed tomography (CBCT) imaging was performed for every participant while awake in the supine position. The anatomical balance was calculated as the ratio of the tongue size to the maxillomandibular enclosure size. The upper airway shape was calculated as the ratio of the anteroposterior dimension to the lateral dimension at the location of the minimal cross-sectional area of the upper airway (CSAmin-shape).

RESULTS

Of 47 participants (28 males, median age [interquartile range] 56 [46 to 63] years, median AHI 27.8 [15.0 to 33.8]), 34 participants were classified as having POSA (72%). The POSA group tended to have a higher proportion of males and a lower AHI than the NPOSA group (P = 0.07 and 0.07, respectively). After controlling for both sex and AHI, the anatomical balance and CSAmin-shape were not significantly different between both groups (P = 0.18 and 0.73, respectively).

CONCLUSION

Adults with POSA and adults with NPOSA have similar anatomical balance and shape of their upper airway in the supine position.

TRIAL REGISTRATION

This study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR Trial ACTRN12611000409976).

The predictive value of mandibular advancement maneuvers during drug-induced sleep endoscopy for treatment success of oral appliance treatment in obstructive sleep apnea: a prospective study

STUDY OBJECTIVES

To prospectively validate drug-induced sleep endoscopy with mandibular advancement maneuvers as a prediction tool for treatment success of oral appliance treatment (OAT).

METHODS

Seventy-seven patients diagnosed with moderate obstructive sleep apnea were included and underwent drug-induced sleep endoscopy. The upper airway collapse was assessed using the VOTE classification. Additionally, three mandibular advancement maneuvers were performed to predict treatment success of OAT. If the maneuver was negative, the level and degree and configuration of the persistent collapse was described according to the VOTE classification. All patients were treated with OAT and completed a follow-up sleep study with OAT in situ without regard to their anticipated response to treatment.

RESULTS

Sixty-four patients completed 6-month follow up. A positive jaw thrust maneuver proved to be significantly associated with favorable OAT response, whereas the chin lift maneuver and the vertical chin lift maneuver were not. Additionally, a persistent lateral oropharyngeal collapse when performing any mandibular advancement maneuver was significantly associated with unfavorable OAT response.

CONCLUSIONS

The current findings suggest that a jaw thrust maneuver should be preferred over the chin lift maneuver for predicting OAT response. Patients with a positive jaw thrust maneuver should be counseled toward favorable OAT response, whereas those with persistent lateral oropharyngeal collapse should be advised about the likelihood of unfavorable OAT response. A negative jaw thrust maneuver did not prove to be a significant predictor for unfavorable response to OAT. Consequently, uncertainties arise regarding the justification of performing drug-induced sleep endoscopy solely for predicting the efficacy of OAT. However, the results of the current study could be influenced by heterogeneity in the assessment of respiratory parameters, variability in the performance of the mandibular advancement maneuvers, and the instability of bolus technique sedation.

CLINICAL TRIAL REGISTRATION

Registry: Netherlands Trial Register; Name: Drug-induced Sleep Endoscopy: a prediction tool for success rate of oral appliance treatment; Identifier: NL8425; URL: https://www.onderzoekmetmensen.nl/en/trial/20741.

CITATION

Veugen CCAFM, Kant E, Kelder JC, Schipper A, Stokroos RJ, Copper MP. The predictive value of mandibular advancement maneuvers during drug-induced sleep endoscopy for treatment success of oral appliance treatment in obstructive sleep apnea: a prospective study. J Clin Sleep Med. 2024;20(3): 353-361.

Effects of mandibular advancement devices on upper airway dimensions in obstructive sleep apnea: responders versus non-responders

STUDY OBJECTIVES

To compare the effects of mandibular advancement device (MAD) therapy on upper airway dimensions between responders and non-responders with mild to moderate obstructive sleep apnea (OSA).

METHODS

Thirty-one participants (21 men and 10 women) with a mean ± SD apnea-hypopnea index (AHI) of 16.6 ± 6.7 events/h, and aged 48.5 ± 13.9 years, were included in this study. Polysomnographic recordings and cone beam computed tomography (CBCT) scans in supine position were performed for every participant at baseline and at 3-month follow-up with their MAD in situ. Responders were defined as having ≥ 50% reduction in baseline AHI with a residual AHI < 10 events/h. The primary outcome variable was the minimal cross-sectional area of the upper airway (CSAmin).

RESULTS

No significant differences were found between responders (n = 15) and non-responders (n = 16) in age, gender distribution, body mass index, and neck circumference (P = 0.06-0.93), nor in AHI and CSAmin (P = 0.40 and 0.65, respectively) at baseline. The changes of the CSAmin with MAD in situ in the responder group were not significantly different compared to those in the non-responder group (P = 0.06).

CONCLUSION

Within the limitations of this study, we conclude that the changes of the upper airway dimensions induced by MADs are not significantly different between responders and non-responders with mild to moderate OSA.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02724865. https://clinicaltrials.gov/ct2/show/NCT02724865.

Self-reported improvement in obstructive sleep apnea symptoms compared to treatment response with mandibular advancement device therapy: a retrospective study

PURPOSE

Mandibular advancement device (MAD) is recognized as the treatment option for management of obstructive sleep apnea (OSA) in mild-moderate cases or those unable to tolerate positive airway pressure therapy. Post-treatment sleep study is recommended to establish MAD efficacy when maximal therapeutic benefit is achieved based on OSA symptom improvement or maximum anatomical protrusion. The aim of this study was to investigate the difference between responders and non-responders in OSA symptom improvement and predictors of treatment success.

METHODS

Medical charts of patients referred to the Orofacial Pain Clinic between 2016 and 2021 for management of OSA with MAD were retrospectively evaluated. Participants with post-treatment sleep study with MAD in situ were included. Participants were categorized as responders according to different criteria: 50% reduction in apnea-hypopnea index (AHI) compared to baseline; post-treatment AHI ≤ 10 with ≥ 50% reduction from baseline; AHI ≤ 5 with ≥ 50% reduction. OSA symptoms included snoring, apneas, sleep quality, tiredness upon awakening, daytime sleepiness, and subjective improvement. Differences in pre- and post-treatment variables within/between groups and predictors were analyzed with t test and logistic regression.

RESULTS

Among 53 participants (30 females), mean age was 64.2 ± 10.7 and pre-treatment was AHI 23.3 ± 17.2. Depending upon the criteria, responders ranged between 26 and 57%. At first follow-up after MAD delivery, non-responders reported less tiredness upon awakening (p = 0.003), better sleep quality (p = 0.005), and greater subjective improvement (p = 0.012) than responders. Among significant OSA symptoms, tiredness upon awakening, poorer sleep quality, and less subjective improvement were consistently found as predictors of treatment response.

CONCLUSION

Subjective improvement, sleep quality, and tiredness upon awakening significantly improved in non-responders at first follow-up compared to responders, according to the strictest definition of treatment response. Therefore, a post-treatment sleep study is crucial to confirm proper management of OSA with MAD.

Multimodal phenotypic labelling using drug-induced sleep endoscopy, awake nasendoscopy and computational fluid dynamics for the prediction of mandibular advancement device treatment outcome: a prospective study

Mandibular advancement device (MAD) treatment outcome for obstructive sleep apnea (OSA) is variable and patient dependent. A global, clinically applicable predictive model is lacking. Our aim was to combine characteristics obtained during drug-induced sleep endoscopy (DISE), awake nasendoscopy, and computed tomography scan-based computational fluid dynamic (CFD) measurements in one multifactorial model, to explain MAD treatment outcome. A total of 100 patients with OSA were prospectively recruited and treated with a MAD at fixed 75% protrusion. In all, 72 underwent CFD analysis, DISE, and awake nasendoscopy at baseline in a blinded fashion and completed a 3-month follow-up polysomnography with a MAD. Treatment response was defined as a reduction in the apnea-hypopnea index (AHI) of ≥50% and deterioration as an increase of ≥10% during MAD treatment. To cope with missing data, multiple imputation with predictive mean matching was used. Multivariate logistic regression, adjusting for body mass index and baseline AHI, was used to combine all potential predictor variables. The strongest impact concerning odds ratios (ORs) was present for complete concentric palatal collapse (CCCp) during DISE on deterioration (OR 28.88, 95% confidence interval [CI] 1.18-704.35; p = 0.0391), followed by a C-shape versus an oval shape of the soft palate during wakefulness (OR 8.54, 95% CI 1.09-67.23; p = 0.0416) and tongue base collapse during DISE on response (OR 3.29, 95% CI 1.02-10.64; p = 0.0464). Both logistic regression models exhibited excellent and fair predictive accuracy. Our findings suggest DISE to be the most robust examination associated with MAD treatment outcome, with tongue base collapse as a predictor for successful MAD treatment and CCCp as an adverse DISE phenotype.

Optimizing Mandibular Advancement Maneuvers during Sleep Endoscopy with a Titratable Positioner: DISE-SAM Protocol

Mandibular advancement devices (MAD) are an effective alternative treatment to CPAP. Different maneuvers were performed during drug sleep-induced endoscopy (DISE) to mimic the effect of MAD. Using the Selector Avance Mandibular (SAM) device, we aimed to identify MAD candidates during DISE using a titratable, reproducible, and measurable maneuver. This DISE-SAM protocol may help to find the relationship between the severity of the respiratory disorder and the degree of response and determine the advancement required to improve the collapsibility of the upper airway. Explorations were performed in 161 patients (132 males; 29 females) with a mean age of 46.81 (SD = 11.42) years, BMI of 27.90 (SD = 4.19) kg/m², and a mean AHI of 26.51 (SD = 21.23). The results showed no relationship between severity and MAD recommendation. Furthermore, there was a weak positive relationship between the advancement required to obtain a response and the disease severity. Using the DISE-SAM protocol, the response and the range of mandibular protrusion were assessed, avoiding the interexaminer bias of the jaw thrust maneuver. We suggest prescribing MAD as a single, alternative, or multiple treatment approaches following the SAM recommendations in a personalized design.

Prediction of Mandibular Advancement Device Response Using CPAP Pressure in Different Polysomnographic Phenotypes

OBJECTIVE

Both continuous positive airway pressure (CPAP) pressure and polysomnographic phenotypes have been associated with mandibular advancement device (MAD) treatment response, but the precise relationship has not been fully elucidated. We hypothesized that utilizing CPAP pressure would predict the MAD response in treatment-naïve patients with moderate-severe obstructive sleep apnea (OSA), and the MAD response would be associated with two polysomnographic phenotypes, including sleep stage dependency and positional dependency.

METHODS

OSA treatment-naïve patients with an apnea-hypopnea index (AHI) ≥15/h who declined CPAP treatment and received MAD treatment for 3-6 months were enrolled. The MAD treatment response was defined as 1) residual AHI under MAD (AHI_MAD) <5/h and 2) AHI_MAD <10/h. Logistic regression was applied to identify the association between CPAP pressure and MAD treatment responders. The predictability of the MAD responder status utilizing CPAP pressure was assessed with the area under the receiver operating characteristic (AUROC).

RESULTS

A total of 128 enrolled patients (AHI ≥30/h in 74.2%) were recruited, of whom 119 patients and 80 patients were included for analysis of sleep stage and positional dependency, respectively. REM-predominant OSA had lower AHI than stage-independent OSA, while the supine-predominant phenotype had lower anthropometrics than the nonpositional-dependent phenotype. The response rates for AHI_MAD <5/h and AHI_MAD <10/h were 25.8% and 48.4%, respectively. Lower anthropometrics, baseline AHI, and supine predominance were associated with the responder status, while CPAP pressure was an independent predictor. The AUROCs for the prediction of AHI_MAD <5/h and AHI_MAD <10/h responders were 0.635 and 0.664, respectively. Utilizing a CPAP level >14 cmH₂O as the cutoff to predict criterion 1 and 2 nonresponders, the sensitivity was 93.9% and 95.2%, respectively.

CONCLUSION

In treatment-naïve patients with moderate-severe OSA, the supine-predominant phenotype and lower CPAP pressure were associated with the MAD response, while the sleep stage dependency phenotype was not. Utilization of a CPAP level >14 cmH₂O could be a sensitive measure to identify nonresponders.

Circadian blood pressure profile and blood pressure changes following oral appliance therapy for obstructive sleep apnoea

OBJECTIVES

Oral appliance therapy for obstructive sleep apnoea (OSA) reduces blood pressure (BP) but there is little information on relationship to circadian BP pattern (nocturnal BP dipping or non-dipping). The aims of this study were to determine whether nocturnal dipping pattern influences BP changes following oral appliance therapy, and to determine the effect of oral appliance therapy on circadian BP pattern.

METHODS

Participants in two randomized trials of oral appliance therapy (1-2 months) with 24-h ambulatory BP monitoring (ABPM) data were included (N = 152). Nocturnal BP Dippers (nocturnal/diurnal SBP ratio <0.9) and non-dippers were compared for BP changes following oral appliance therapy and the effect of oral appliance therapy on nocturnal BP dipping was assessed.

RESULTS

Of 152 participants, 64.5% were dippers. Dippers were on average younger and less likely to be hypertensive (42 vs. 82.7%, P < 0.001). Nondippers showed greater reduction in nocturnal BP measures, related to higher BP measures at baseline. There was no difference in the relationship between treatment effectiveness and BP changes between groups. Oral appliance therapy converted only 23% of baseline non-dippers to a nocturnal dipping profile.

CONCLUSION

Baseline circadian BP profile influenced the BP response to oral appliance therapy, largely because of higher baseline BP in the non-dipper subgroup. Oral appliance therapy did not convert OSA patients to a more favourable circadian BP profile. Further work is required to understand the effect of oral appliance therapy on circadian BP profile and of the individuals who will receive cardiovascular benefit from oral appliance therapy.

The predictive value of drug-induced sleep endoscopy for treatment success with a mandibular advancement device or positional therapy for patients with obstructive sleep apnea

PURPOSE

As drug-induced sleep endoscopy (DISE) can provide additional diagnostic information on collapse patterns of the upper-airway, it is widely used in patients with obstructive sleep apnea (OSA). Although more controversial, DISE may also predict the success of treatment with a mandibular advancement device (MAD) and/or positional therapy (PT). In 2018, we proposed a prediction model to investigate the predictive value of passive maneuvers during DISE - such as jaw thrust and changes in body position - on upper-airway patency. Based on the outcomes of various studies, we then adjusted our DISE protocol to better mimic the effect of a MAD, PT, or a combination of both. The aim of this study was to verify whether or not our adjustments would increase the value of DISE as a selection tool.

METHODS

This single-center retrospective cohort study involved a consecutive series of patients with OSA. Patients were included if a DISE had been performed in supine and non-supine sleeping position and with and without a boil-and-bite MAD in situ between December 2018 and February 2020. The VOTE scoring system was used to evaluate the obstruction at four levels of the upper-airway.

RESULTS

Among 94 patients included. the median apnea-hypopnea index (AHI) was 16.2 (events/h). As a temporary MAD during DISE reduced obstruction by 54% and jaw thrust by 57%, both mimicked the effect of the custom-made MADs referred to in the literature, which reduces the AHI by 60%. Head-and-trunk rotation reduced obstruction by 55% and thus mimicked the effect of PT, which is known to reduce the AHI by 50%.

CONCLUSION

A jaw thrust, a temporary MAD, and head-and-trunk rotation during DISE all seem to mimic the treatment effects of MAD and PT. These findings may be of added value when choosing OSA treatment. To prove the predictive value of these maneuvers during DISE, a prospective study should be performed.

The relationship between specific nasopharyngoscopic features and treatment deterioration with mandibular advancement devices: a prospective study

STUDY OBJECTIVES

The variable efficacy of mandibular advancement device (MAD) treatment necessitates both accessible and accurate methods for patient selection. However, the role of awake nasopharyngoscopy for this purpose remains dubious. We introduced an assessment method based on anatomical upper airway features during tidal breathing for nasopharyngoscopy. The current study aimed to relate these features to MAD treatment outcome.

METHODS

One hundred patients diagnosed with obstructive sleep apnea were prospectively recruited for MAD treatment in a fixed 75% degree of maximal protrusion. Nasopharyngoscopic observations during Müller's maneuver and tidal breathing were recorded both with and without MAD. Treatment outcome, confirmed by 3-month follow-up polysomnography with MAD, was classified as (1) apnea-hypopnea index reduction ≥ 50%, (2) treatment apnea-hypopnea index < 5 events/h, and (3) ≥ 10% increase in apnea-hypopnea index compared with baseline (treatment deterioration).

RESULTS

A complete dataset was obtained in 65 patients. After adjusting for baseline apnea-hypopnea index, body mass index, and supine dependency, the position of the soft palate (odds ratio, 4.0; 95% confidence interval, 1.3-11.8; P = .013) and crowding of the oropharynx (odds ratio, 7.7; 95% confidence interval, 1.4-41.4; P = .017) were related to treatment deterioration. Addition of both features significantly (P = .031) improved the accuracy of baseline models based on clinical measurements alone. Moreover, with the MAD in situ, a posteriorly located soft palate (odds ratio, 9.8; 95% confidence interval, 1.7-56.3; P = .010) and a posteriorly located tongue base (odds ratio, 7.4; 95% confidence interval, 1.5-35.9; P = .013) were associated with treatment deterioration.

CONCLUSIONS

Awake nasopharyngoscopy might be a valuable office-based examination to exclude the risk of treatment deterioration and improve patient selection for MAD treatment.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Predicting Therapeutic Outcome of Mandibular Advancement Device Treatment in Obstructive Sleep Apnea (PROMAD); URL: https://clinicaltrials.gov/ct2/show/NCT01532050; Identifier: NCT01532050.

A consideration of factors affecting palliative oral appliance effectiveness for obstructive sleep apnea: a scoping review

STUDY OBJECTIVES

This scoping review allows physicians, researchers, and others interested in obstructive sleep apnea to consider effectiveness of oral appliances (OAs). The intent is to improve understanding of OA effectiveness by considering morphologic interaction in patients with obstructive sleep apnea.

METHODS

Morphologic and biomechanical criteria for positional alterations of the mandible assessed success rates of OA appliances. Searches of databases (Medline, PubMed, The Cochrane Library, EBSCO) using terms: OA treatment effectiveness and positive and/or negative outcome predictors. Craniofacial predictors of OAs and obstructive sleep apnea biomechanical factors of anatomical traits associated with OA effectiveness were included. Databases searched radiographic cephalometric imaging for morphology/phenotypes and apnea-hypopnea index responses. Articles were excluded if title or abstract was not relevant or a case report. If the analysis did not report mean or standard deviation for apnea-hypoxia index, it was excluded. No language, age, or sex restrictions were applied.

RESULTS

Analysis of 135 articles included in searched literature indicated alterations in musculature and pharyngeal airway structure through OA use. These alterations were individually unpredictable with wide variability 61.81% ± 12.29 (apnea-hypoxia index mean ± standard deviation). Morphologic variations as predictors were typically weak and idiosyncratic. Biomechanical factors and wide variations in the metrics of appliance application were unclear, identifying gaps in knowledge and practice of OAs.

CONCLUSIONS

An integrated basis to identify morphologic and biomechanical elements of phenotypic expressions of sleep-disordered breathing in the design and application of OAs is needed. Current knowledge is heterogeneous and shows high variability. Identification of subgroups of patients with obstructive sleep apnea responding to OAs is needed.

Acoustic pharyngometry - A new method to facilitate oral appliance therapy

Background

There is lack of reliable and accurate methods to predict treatment outcomes of oral appliance (OA) treatment. Acoustic pharyngometry (AP) is a non‐invasive technique to evaluate the volume and minimal cross‐sectional area of the upper airway, which may prove useful to locate the optimal position of OAs.

Objective

This retrospective study aimed to evaluate the effect of applying AP to OA treatment of patients with obstructive sleep apnoea (OSA).

Methods

All patients (n = 244) treated with OAs following an AP protocol at two dental clinics between 2013 and 2018 were invited to participate. A total of 129 patients accepted the invitation, and 120 patients (75 men, 45 women) were included in the analyses. Mean baseline age, BMI and apnoea hypopnea index (AHI) were 59.1 ± 0.9 years, 27.8 ± 0.4 and 21.9 ± 1.1, respectively. Mean follow‐up time was 318 ± 24 days.

Results

AHI at follow‐up was 6.4 ± 0.7, resulting in a treatment success rate of 86.7% (≥50% reduction of baseline AHI). The number of failures (<50% reduction of baseline AHI) did not differ significantly among patients with mild, moderate and severe OSA. 87.6% of the patients reported OA usage every night, and 95.5% reported > 5 hours usage per night, when worn.

Conclusion

The AP protocol applied seems to contribute to the excellent effect of OA treatment in this study. Further research on the application of AP in OA treatment is necessary in order to clarify its possible beneficial contribution to improving OA therapy.

The role of sleep endoscopy in oral appliance therapy for obstructive sleep apnea

OBJECTIVE

Although oral appliance therapy is considered a validated treatment for obstructive sleep apnea, its therapeutic success varies significantly among patients. Drug-induced sleep endoscopy is often employed in order to identify candidates for upper airway surgery; however, it remains unknown whether its findings can be associated with success of oral appliance therapy. This study tested the hypothesis that drug-induced sleep endoscopy variables can predict the outcome of oral appliance therapy in obstructive sleep apnea patients.

METHODS

Forty-nine obstructive sleep apnea patients [45 men; mean apnea-hypopnea index 25.3 ± 7.5 events/h; mean body mass index 28.2 ± 3.0 kg/m²] underwent drug-induced sleep endoscopy, followed by a one-month of oral appliance therapy, and subsequently a follow-up polysomnography to assess outcome.

RESULTS

Thirty-three patients (67.3%) were responders and sixteen were non-responders (32.6%). Non-responders had a higher occurrence of complete or partial circumferential collapse at velum in comparison with responders. Multivariate logistic regression analysis revealed that, among baseline clinical and polysomnographic characteristics and sleep endoscopy findings, the presence of complete circumferential collapse at velum and increased body mass index were the only independent predictors of oral appliance therapy failure.

CONCLUSION

Drug-induced sleep endoscopy can be used to predict a higher likelihood of success to oral appliance therapy in obstructive sleep apnea patients.

The success rate of oral appliances based on multiple criteria according to obstructive sleep apnoea severity, BMI and age: A large multicentre study

BACKGROUND

The efficacy of oral appliance (OA) varies greatly in patients with obstructive sleep apnoea (OSA).

OBJECTIVE(S)

The purpose of this cross-sectional study was to investigate the success rate of OA for OSA patients.

METHODS

This study was based on a cross-sectional multicentre survey of OA therapy for the management of OSA called the JAMS (Japanese Cross-sectional Multicenter Survey) Study performed at 10 medical institutions. A total of 442 patients fulfilled the selection criteria, which patients had worn OA, and undergone overnight polysomnography to assess both the pre-treatment baseline and follow-up for OA. Age, sex, BMI and apnoea-hypopnea index (AHI) at the time of diagnosis and follow-up for OA were extracted.

RESULTS

After OA treatment, the mean AHI decreased from 22.6 ± 13.8 to 10.0 ± 10.2/h, and the mean rate of decrease in the AHI was 52.5 ± 38.4%. Regarding the success rate to OA therapy, criterion 1 (AHI < 5/h), criterion 2 (AHI < 10/h), criterion 3 (AHI < 15/h) and criterion 4 (AHI reduction rate ≥ 50%) accounted for 33.5, 66.3, 80.5 and 63.3%, respectively. The success rate of OA treatment decreased according to the increase in OSA severity, obesity level (higher BMI) and older age.

CONCLUSIONS

This study revealed the treatment success rate of OA on multiple criteria according to OSA severity, BMI and age. It may support for the clinician to make a decision on the OSA management.

Oral Appliance Therapy for Obstructive Sleep Apnoea: State of the Art

Obstructive sleep apnoea (OSA) represents a significant global health burden, with impact on cardiometabolic health, chronic disease, productivity loss and accident risk. Oral appliances (OA) are an effective therapy for OSA and work by enlarging and stabilising the pharyngeal airway to prevent breathing obstructions during sleep. Although recommended in clinical guidelines for OSA therapy, they are often considered only as second-line therapy following positive airway pressure (PAP) therapy failure. There has been a long-standing barrier to selecting OA over PAP therapy due to the inability to be certain about the level of efficacy in individual OSA patients. A range of methods to select OSA patients for OA therapy, based on the outcome of a single sleep study night, have been proposed, although none has been widely validated for clinical use. Emergent health outcome data suggest that equivalent apnoea–hypopnea index reduction may not be necessary to produce the same health benefits of PAP. This may be related to the more favourable adherence to OA therapy, which can now be objectively verified. Data on longer term health outcomes are needed, and there are additional opportunities for device improvement and combination therapy approaches. OAs have an important role in precision care of OSA as a chronic disorder through a multi-disciplinary care team. Future studies on real-world health outcomes following OA therapy are needed.

Polysomnographic Endotyping to Select Patients with Obstructive Sleep Apnea for Oral Appliances

Rationale: Oral appliance therapy is efficacious in many patients with obstructive sleep apnea (OSA), but prediction of treatment outcome is challenging. Small, detailed physiological studies have identified key OSA endotypic traits (pharyngeal collapsibility and loop gain) as determinants of greater oral appliance efficacy.Objectives: We used a clinically applicable method to estimate OSA traits from routine polysomnography and identify an endotype-based subgroup of patients expected to show superior efficacy.Methods: In 93 patients (baseline apnea-hypopnea index [AHI], ≥20 events/h), we examined whether polysomnography-estimated OSA traits (pharyngeal: collapsibility and muscle compensation; nonpharyngeal: loop gain, arousal threshold, and ventilatory response to arousal) were associated with oral appliance efficacy (percentage reduction in AHI from baseline) and could predict responses to treatment. Multivariable regression (with interactions) defined endotype-based subgroups of "predicted" responders and nonresponders (based on 50% reduction in AHI). Treatment efficacy was compared between the predicted subgroups (with cross-validation).Results: Greater oral appliance efficacy was associated with favorable nonpharyngeal traits (lower loop gain, higher arousal threshold, and lower response to arousal), moderate (nonmild, nonsevere) pharyngeal collapsibility, and weaker muscle compensation (overall R2 = 0.30; adjusted R2 = 0.19; P = 0.003). Predicted responders (n = 54), compared with predicted nonresponders (n = 39), exhibited a greater reduction in AHI from baseline (mean [95% confidence interval], 73% [66-79] vs. 51% [38-61]; P < 0.0001) and a lower treatment AHI (8 [6-11] vs. 16 [12-20] events/h; P = 0.002). Differences persisted after adjusting for clinical covariates (including baseline AHI, body mass index, and neck circumference).Conclusions: Quantifying OSA traits using clinical polysomnography can identify an endotype-based subgroup of patients that is highly responsive to oral appliance therapy. Prospective validation is warranted.